Fuel supply control mechanism for gas burners



0a. 21, 1931. G. A. TUCK 1,828,883

FUEL SUPPLY CONTROL MECHANISI FOR'GAS BURNERS Filed June 26. 1929 3 Sheets-Sheet l 23 lurzlvro'fi 0a. 27, 1931. G, A, TU K 1,828,883

FUEL SUPPLY CONTROL IECHANISI FOR GAS BURNERS Filed June 26. 1925 3 Sheets-Sheet 2 G. A. TUCK 1,828,883

FUEL SUPPLY CONTROL NECHAKISI FOR GAS BURNERS Filed June 26, 1929 3 Sheets-Sheet 3 Patented Oct. 27, 1931 PATENT OFFICE GEORGE A. TUCK, OF SAN FRANCISCO, CALIFORNIA FUEL SUPPLY CONTROL MECHANISM FOR GAS BURNERS Application filed June 26,

My invention relates to improvements in mechanism to automatically control the supply of fuel to a gas burner wherein means actuated thermostatically by a pilot burner operates to shut oifthe supply of fuel to the burner and to the pilot in event the pilot light becomes extinguished. I

The primary object of my invention is to provide an improved mechanism for automatically shutting off the supply of fuel to a gas burner in event the pilot burner for said gas burner becomes extinguished.

Another object is to provide an improved mechanism wherein the supply of fuel to the pilot is shut off simultaneously with the shutting off of the main fuel supply to prevent fuel from issuing from said pilot and collecting unburned within'a furnace.

-A further object is to provide an improved 53 mechanism of the character described which will operate with increased speed and efficiency. I

Another object is to provide an improved device wherein a pilot may be supplied with 33 fuel taken from either the supply side or the deliver side of a main shut-ofi valve and adapte to retain said shut-off valve in open position only when the supply is taken from the delivery side of said valve whereby a closing of said valve will operate to shut off the supply of fuel to the pilot.

Another object is to provide an improved control mechanism which is sim 1e and positive in its action and which is 001 proof in its operation. A further object is to provide an improved thermostatic actuating member adapted to utilize heat from the main burner to provide a differential expansion and contraction affording increased speed and degree of movement.

Another object is to provide an improved valve setting and retaining means of simple and rugged construction, requiring no delicate parts or adjustments, and which may be economically made and installed;

A still further object is to provide an improved pilot control valve adapted to prevent interruption to the supply of fuel when turned from a starting to a service position.

1929. Serial No. 373,855.

' I accomplish these and other objects by means of the improved device disclosed in the drawings-forming apart of the present application wherein like characters of reference are used to designate similar parts ll throughout the specification and drawings, and in which i Fig. 1 is a broken front elevation of my improved fuel supply control mechanism;

Fig. 2 is a broken plan view of the mecha- N nism as shown in Fig. 1;

Fig. 3 is a broken side mechanism;

' Fig. iis a broken horizontal section of the valve setting and releasing means and U the pilot valve associated therewith, the figure being drawn upon a larger scale; Fig. 5 is a broken front view of the mecha- 'nism shown in Fig. 4 with the pilot valve set in starting position; 1

Fig. 6 is a side elevation of the device as shown in Figs. 4 and 5, the pilot valve being omitted;

Fig. 7 is a view similar to Fig. 4 with the I pilot valve in service position and the main valve setting means set in valve opening poelevation of said sition; A

Fig. 8 is a broken longitudinal section of the pilot burner and thermostatic actuating mechanism; and Fig. 9 is an enlarged sectional detail of the pilot valve.

Referring to the drawings, the numeral 1 is used to designate in general a gas burner of any operative form and construction to which fuel is su plied through a main supply connection 2 aving a main shut-off valve 3 operable to shut off the supply. of fuel through said connection 2. The valve 3 is provided with an actuating member 4 secured upon the stem of the valve and provided with a weight 6 adapted to normally be moved by gravity to close the valve; Valve setting and controlling mechanismis mounted in a convenient position adjacent the front of the burner 1, said mechanism comprising a mounting plate 7 having outwardly extending brackets 8 and 9 formed at the top and bottom thereof respectively.- A pilot manifold 11 is mounted upon the back of the plate 7 ,said manifoldextending along the side of the burner 1 and being provided with a'pilot burner 12 having openings 13 adapted to project a flame onto the burner to ignite fuel issuing from the burner in the ordinary manner. The manifold preferably constructed as a relatively long tubular member threaded as at 14 into an opening formed in the plate 7, the burner 12 being positioned approximately midway of its length whereby heat from the pilot flame issuing from the openings .13 will be conducted rapidly along the full length of the tubular manifold.

Fuel is delivered to the pilot manifold 11 through a tubular connection 16 connected between said manifold and the outlet port 17 of a three-way pilot valve 18. The valve 18 is provided with the usual plug 19 movable to direct fuel to the outlet 17 from either "of a pair of inlet ports 21 and 22. The port 21 is connected to the main fuel supply connection 2 by a pilot supply connection 23 opening into the connection 2 at a point ivery side of the valve 3. A passage 26 is lower end of the member 27.

3 upon the supply side of the valve 3,"the

' connection 23 being hereinafter referred to as the pilot starting connection. The port 22 is connected to the connection 2 through a service connection 24 opening into the main supply connection 2 at a point upon the deformed in the valve 18 between the service inlet 22 and .the outlet 17 to permit an un interrupted flow of 'fuel to the pilot while the plug 19 is being moved from a starting position, as shown in full lines in Fig. 9, to its service position,.as indicated in dotted lines in said figure.

A valve setting member 27 is slidably mounted uponthe plate'7, said member 27 extending upwardly through the upper bracket 8 and being guided by suitable guide means 28 positioned upon the front of the plate 7 substantially midway between the brackets 8 and 9. A flexible connecting member 29 is secured to the upper end of the member 27 and extended over suitable guides 31 to the valve actuating member 4, as in- A latch 32 is pivotally mounted upon the The latch 32 is mounted in unbalanced position whereby the latch will normally be moved by gravity to hang in a substantially vertical osition. The heavy end-of the latch is provi ed with a rounded corner '33 adapted toen age a chamfered surface 34 of :1 lug 34 ormed upon the bottom bracket 9 to swing the latch out of its vertical position when the member ;27 is moved to its lowermost position as indicated in full lines in F1g. 5 of'the drawings.

The upper end of the latch 32 consists of a relatively thin" extension 36 adapted to be moved under the edge of a stop-37 pivotally re eases .9 in spaced relation to said lug 34. The stop 37 is provided with an extension 37' forming a 'detent for the latch extension 33, and also provided with an outwardly disposed extension 37 having a notch 39 formed upon the under side thereof.

A lever 41 is pivotally mounted at its lower endbetween the lug 38 and a similar .lug 42 spaced therefrom upon the bracket 9, said lever being pivotally movable upon the pivot pin 35 which is extended through the lugs 34, 38, and 42 to pivotally support both the stop 37 and the lever 41. The upper end of the lever 41 is linked to a lever 44 by means of a yoke 46 pivotally connected to both levers. The lever '44 is pivoted upon a pin 47 extending between lugs 48 formed upon the lower face of the upper b'racket'S.

The lower end of the lever 44 is provided with a laterally disposed arm 49 extending under the extension 37" and supporting the stop 37. The arm 49 is so positioned that when thelower edge of the extension 37 rests upon the arm 49, the stop will be supported in an operative position as indicated in full lines in. Fig. 6 of the drawings. An outward movement of the'lower end of the lever 44 permits the arm 49' to be engaged.

within'the notch 39, thereby permitting the stop 37 to tip to an inoperative position, dis-. engagin the latch 32, as indicated in dotted lines in ig. 6.

The levers 41 and 44 are actuated by thermostatic means energized by the pilot burner 12. This is accomplished by-means of a rod 51 extending longitudinally through the pilot manifold 11. The rod is secured to the inner end of the manifold 11 by means of a plug 52 threaded into the end of the manifold tube and internally threaded to receive the rod 51 An extension 53 of the rod 51 extends longitudinally outwardly from the end of the manifold tube and isslidably supported within a lug 54 formed upon the burner 1 to form a support for the inner end of the manifold and toronduct heat from the burner to the rod 51. At the forward end of themanifold '11, the rod 51 extends outwardly through a plug 56 threaded into the end of the manifold and having an aperture 57 forming a close sliding fit with the end of the rod whereby said rod may be moved longitudinally relative to the manifold and plug without permitting the escape of gas past the rod. The end of the rod 51 extends Leas es from the plug 19 of the pilot valve 18. The stop 58 is movable with the plug 19 and is segmental in shape. When the valve 18 is set to deliver fuel from the starting connection 23, the stop 58 is moved to an inoperative position away from the latch 32, as

shown in Fig. 5 and in full lines in Fig. 9 of f the drawings. When the valve is moved to close the starting connection 23 and open the service connection 24, ,the stop .is moved to a position adjacent to and on a level with the lower edge of the stop extension 37, as shown in Fig. 7, and in dotted lines in Fig. 9' of the drawings. K

The plate 7 is secured in any suitable manner upon the front of a furnaoe or other device, not shown, adjacent the burner and gas supply connection thereof,- in substantially the relation disclosed.

In operation, the pilot valve 18 is initially set to deliver fuel from the starting connec-.

' tion 23 to the pilot. With the pilot burner 12 lighted, heat from the flame of said ilot quickly heats the pilot burner 12 and' eat from said burner is conducted along the length of the tubular manifold 11, thereby causing said manifold to expand. As the manifold 11 expands, the rod 51 is moved longitudinally inwardly away from the lever 41, thereby permitting the levers 44 and 41 to be moved toward the plate 7 by the tension of a light spring 61. connected between the lever 44 and the plate 7 L The stop 37 is then raised manually from its inoperative position, as indicated in dotted lines in Fig. 6 to its operative position shown in full lines,

. the movement of the lever 44 causing the arm 49 to move inwardly past the notch 39 and permit the lower edge of the extension 37" to be supported directly upon said arm 49, thereby holding the stop 37 in its raised operative position.

The valve setting member 27 is then moved downwardly from the position indicated in dotted lines in Fig. 1 to its lowermost position, thereby causing the flexibleconnection 29 toraise the arm 4 and weight 6 to a raised valve opening position as indicated in full lines in said figure. As the valve 3 is opened, fuel is admitted to the gas burner 1 and is ignited by the pilot in the usual manner.

As the member 27 approaches its lowermost osition, the latch 32 strikes against the cham ered face 34 and is swung from its normal vertical position to an inclined position with the end of the extension 36 extending under the extension 37 so that when the member is again moved upwardly, either manually or by the weight 6, said extension 36will engage tlie extension 37 and swing the latch toward a horizontal position.

While the pilot valve 18 is set in its starting position, the latch is free to swing upward- 1y, as indicated, through the light dotted position indicated in Fig. 5 and carried upwardly past the stop 37 to a position su'chas indicated in heavy dotted lines in Fig. 5, thereby preventing the latch from operating to hold the valve setting member in its valve opening position. The latch 32 may remain in an inverted position after passing the stop 37, as indicated in Fig. 5. The end of the extension 36 is therefore chamfered, as at 36' so that as the member 27 is again moved downwardly to its lowermost position, the point of said extension 36 will engage the upper end of the. lug 34 and return the latch to normal position.

In order to secure the valve setting member 27, and the valve 3 in open position, it is necessary to turn the pilot valve .18 to its service position, as indicated in Figs. 1, 4, and 7. When the valve 18 is set inthe service posi'ion, the sector 58 is swung to a position such that as the latch 32 is swung up to a horizontal position by a slight upward movement of the member 27, theend of the latch will engage the sector and prevent further, upward movement of the member 27, thereby holding the arm 4 in raised, or. valve opening position.

The valve 18 is preferably turned to s-erv ice position after the member 27 has been moved downwardly to open the main valve 3 so that when the member 27 is released it will be immediately engaged and. held in operative position by the stop 58. To prevent extinguishing the pilot light at the instant the supply of fuel from the starting connection 23 is cut off, the passage 26 is provided, there-- by permitting the connection 24to become filled with fuel while the passage 23 is open. As'the valve 18 is moved to service position, sutficient fuel will issue through the passage 26 to the pilo to keep the same burning until the valve 18 is fully moved to its service position.

When the valve 18 is moved to service position, the starting connection 23 is fully closed so that no fuel can pass from-the supply side of the connection 2 to the pilot. So long as the pilot burner 12 remains burning heat from its flame operates to keep the man ifold expanded and the rod 51 receded. and

the levers 44 and 41' will be held in the po- '44 servicev position. Thereafter, the rod 1 51 will gradually become heated but the degree of movement resulting from' the expansion of the rod 51 alone after the tube 11 has been fully expanded is not sufficient to e flect a release of the valve setting mechanlsm and in their fully heated and expanded condition, the manifold tube 11 and rod 51 permit the levers to remain in service position.

In event the pilot light becomes extinguished, the tubular manifold 11 will immediately begin to cool and contract, there by moving the rod 51 outwardly against the lever 41 and causing said lever 41 to be moved outwardly to the positionindicated in dotted lines in Fig. 3. The movement of the rod 51 is multiplied by the length of the lever 41 and the movement at the upper end of said lever 41 is again multiplied as it is imparted to the lever 44 by the link 46 so'that at the lower end of said lever 44 a relatively great movement of the arm 49 results from a very slight movement of the rod 51. As the lever 44 is moved outwardly to its valve closing position, as indicated in dotted lines in Figs. 3 and 6,-the arm 49 is moved opposite the notch 39, thereby permitting the stop 37 to drop to its latch releasing position as indicated in-said figures. This movement of the stop 37 permits the thin extension 36 of the latch 32 to passthe end of the extension 37 thereby permitting the member 27 to bemoved freely upwardly and the valve 3 to be closed by the action of gravity upon the weight.

When the valve 3 is closed as above described, the supply of fuel to the pilot burner 12 is cut off simultaneously with the supply to the burner 1. This is important, as heretofore pilot burners have commonly been supplied from a service connection so that fuel tinguished at the instant the main burner is extinguished and if fuel is permitted to issue unburned from the pilot into a furnace and around the heated burner an explosive mixture may be produced and ignited-with very serious results. Furthermore, it is important g that the fuel be shut off very quickly after the burner and'pilot have been ex inguished as unburned gas accumulating from the pilot burner in the hot furnace may quickly produce an explosion. To insure a quick closing of the valve 3 after the pilot is extinguished, I provide the extension 53 which is extended into contact with the lug 54 of the burner 1. Heat from the burner 1 will thus be imparted directly to the rod 51 .to maintain said rod in a heated and expanded condition for a substantial period of time after the burner 12 is extinguished and the manifold 11 caused to cool. The manifold tubell cools relatively fast after the burner 12 is extinguished, and the full movement due to the contraction of the cooling manifold will be rendered effective for actuating the levels 41 and 44 before said movement iscounteracted by a corresponding cooling and contraction of the valve 3 is of course independification in numerous specific details, and I therefore desire to avail myself of all such modifications as may fall within the scope of the appended claims.

. Having thus described my invention, what I claim as new and desire to secure by Letters Patent is-- 1. A fuel supply control mechanism comprising the combination with a gas burner provided with a fuel supply connection having a main valve movable to shut ofi the supply of fuel to the burner, of means for normally moving the valve to closed position; a pilot mounted adjacent the burner; pilot fuel supply connections connecting the pilot with the burner supply connection upon opposite sides of the main valve; valve means for directing fuel from either pilot supply connection to the pilot; latch means for holdv ing the valve closing means in open position when the pilot is burning and to automatically release said closing means to valve closing position when the pilot is extinguished; and means actuated by the pilot valve to render the latch means operative when fuel is directed from the delivery side of the main valve to the pilot and for rendering said latch means inoperative when said pilot valveis set to direct fuel from the supply side of saidmain valve to the pilot.

2. A fuel supply control mechanism comprising the combination with a gas burner provided with a fuel supply connection having a main valve movableto shut ofi' the supply of fuel to the burner, of valve actuating means for normally moving the valve to a closed position; a pilot mounted adjacent the burner; pilot fuel supply connections connecting the-pilot with the burner fuel supply connection upon opposite sides of the main valve; valve means for directing fuelfrom either of said pilot supply connections to the pilot; a member connected to the valve actuating means and provided with a latch; a stop mounted to normally-engage the latch when the member and valve actuatand means movable with the pilot valve to.

engage and hold the latch in engagement with the stop when said valve is set to deliver fuel to the pilot from the delivery side of the main valve, and to permit movement of the latch past said stop when said valve is set to deliver fuel to the pilot from the supply side of said main valve.

3. A fuel supply control mechanism com prising the combinationwith a gas burner provided with a fuel supply connection having a main valve movable to shut off the supply of fuel to the burner, of valve actuating means for normally moving the valveto a closed position; a pilot mounted adjacent is extinguished; and means for rendering the the burner; pilot fuel supply connections connecting the pilot-with the burner fuel supply connection upon opposite sides of the main valve; valve means for directing fuel from either of said pilot supply connections to the pilot; a member connected to the valve actuating means and provided with a latch; a stop mounted to normally engagethe latch when the member and valve actuating means are in valve opening position; means for holding the stop in operative position when the pilot is burning'and for automatically releasing said stop to an inoperative position when the pilot is extinguished; means movable with the pilot valve to engage and hold the-latchin engagement with the stop when said valve is set to deliver fuel to the pilot from the delivery side of the main valve, and to permit movement of the latch past said stop whensaid valve is set to deliver fuel to the pilot from the supply side' of said main valve; and a passage formed in the pilot valve to permit a continued supply of fuel to the "pilot when said valve is moved to close the supply connection to the supply side of-tlie main valve.

4. A fuel supply control mechanism comprising the combination with a gas burner provided with a fuel supply connection having a main valve'movable to shut oil the supply of fuel to the burner, of valve actuating means for normally moving the valve to a closed position; a pilot mounted adjacent the burner; pilot fuel supply connections connected to the burner supply connection upon opposite sides of the main valve; a three-way valve connected with the pilot and with the supply connections and movable to direct fuel from either of said supply connections to'the pilot; a valve setting member connected to the main valve actuating means and movable to valve opening and closing positions; a. latch pivotally mounted upon said member;

a stop pivotally mounted adjacent the pilot valve and movable.- to engage one end of said latch when the member is in-valve opening position; ther'mostz'it-icv means energized by heat from the pilot for normally holding the stop in operative position and to release said stop to an inoperative position when the pilot .guished.

means for normally moving-the valve to aclosed position; a pilot mounted adjacent the burner; pilot fuel supply connections connected to the burner supply connection upon opposite sides of the main valve; a three-way valve connected with the pilot and with the supply connections and movable to direct fuel from either of said supply connections to the pilot; a valve setting member connected to the main valve actuating means and movable to valve opening and closing positions; a latch mounted upon said member; a stop movable to engage the latch when the valve setting member is'in valve opening position a second stop movable with the pilot valve to hold the latch in engagement with the first stop when the pilot valve is set to direct fuel from the delivery side of the main valve to the pilot, and to permit free movement of the latch past said stops when said pilot valve is set to direct fuelfrom the supply side of said main valve .to the pilot; and thermostatically actuated means for releasing the latch when the pilot is extin- 6. A fuel supply mechanism comprising .the combination with a gas burner provided with a fuel supply connection having a main Valve movable to shut off the supply of fuel to the burner, of means for normally moving the valve to a closed position; a pilot manifold mounted adjacent the burner and provided with a pilot burner to direct a flame to said burner; a three-way pilot valvehaving a connection opening into the pilotmanifold; a pair of pilot supply connections connecting the valve with the main fuel supply connection upon opposite sides of the main valve; a a valve setting member connected to the main valve; a latch mounted upon said setting member; a stop movable to an operative position to engage the la ch when the setting member is in valve opening position; a control lever provided with an arm s upporting the stop-in its operative position;

thermostatic means for moving the lever to release the stop to an inoperative position when the pilot burner is extinguished; and a safety stop movable with the pilot valve to hold the latch in engagement with the first stop whenthe pilot valve is set to direct fuel from the delivery side of the main valve to the pilot, and to permit free movement of the latchpast the stops when said pilot valve is set to direct fuel from the supply side of said main valve to the pilot.

7. A. fuel supply control mechanism comtion upon opposite sides of the main valve;

a main valve setting member connected to the valve closing means; a latch mounted upon said member; a stop pivotally mounted to engage and disengage the latch; a stop lever having an arm supporting the stop; a rod extending longitudinally through the pilot manifold and movable by the expansion and contraction of the pilot manifold due to heat for actuating the stop lever to support the stop in its operative position when the pilot burner is burning and to release said stop todisengage' the latch when the pilot burner is extinguished and a safety stop actuated by the pilot valve to hold the latch in normal engagement with the first stop when said valve isset to direct fuel from the delivery side of the main valve, and to permit free 'movement of the latch past-the stop when said pilot valve is set to direct fuel from the supply side of said main valve.

8. A fuel supply control mechanism comprising the combination with a gas burner rovided with a fuel supply connection havmg a main valve movable to shut off the sup ply of fuel to the burner, of means for normally moving the valve to a closed position; a pilot manifold mounted adjacent the burner and provided with a pilot burner to direct a flame to the main burner; a three-way pilot valve having a connection to the pilot manifold; a pair of pilot supply connections connecting the valve to the main supply connection upon opposite sides of the main valve; a main valve setting member connected to the valve closing means; a. latch mounted upon said member; a stop pivotally mounted to engage and disengagethe latch; a stop lever having an arm supporting the stop; a 'rod ex tending longitudinally through the pilot manifold and movable by the expansion and contraction of the pilot manifold due to heat for actuating the stop lever to support the stop in its operative position when the pilot burner isburning and to release said stop to disengage the latch when the pilot burner is extinguished; and a safety stop actuated by the p1lot valve to hold the latch innormal engagement with the first stop when said va ve is set to direct fuel from the delivery side of the main valve, and to permit free movement of the latch past the stop when said ilot valve is set to directfuel from the supp y side of said main valve; and means for conducting heat from the main burner to the rod to retard the contracting of said rod when the pilot burner is extinguished.

9. A fuel supply control mechanism comprising the combination with a gas burner provided with a fuel supply connection having a main valve movable to shut off the supply of fuel to the burner, of means for normally movingthe valve to a closed position; a valve setting member connected to the valve closing means; a latch mounted upon the valve setting member; a stop movable to engage and disengage the latch; lever means engaging the stop to support said stop in latch engaging position and movable to release said stop to latch releasing position; a pilot manifold mounted adjacent the burner and provided with apilot burner; a pilot supply connection connecting the pilot manifold with the main fuel supply connection upon the delivery side of the main valve; and means actuated by contraction of the pilot manifold when the pilot burner is extinguished to move the stop lever means to release the stop and disengage the latch whereby the supply of fuel to the burner and tothe pilot are automatically shut off when the pilot becomes extinguished.

10. A fuel supply control mechanism comprising the combination with a gas burner provided with a fuel supply connection having a main valve movable to shut off the supply of fuel to the burner, of means for normally moving the valve toa closed position;- a valve settingmember connected to the valve closing means; a latch mounted upon the valve setting member; a stop movable to engage'and disengage the latch; lever means engaging the stop to support said stop in latch engaging position and movable to release said stop to latch releasing position; a pilot manifold mounted adjacent the burner and provided with a pilot burner; a pilot supply connection connectmg the pilot manifold with the main fuel supply connection upon the delivery side of the main valve; means actuated by contraction of the pilot manifold when the pilot burner is extinguished to move the stop lever means to release the stop and dis-v engage the latch whereby the supply of fuel to the burner and to the pilot are automaticallyshut off when the pilot becomes extinguished; a vvalve controlled pilot starting connection connecting the pilot with the fuel supply connection upon the supply side of v the main valve; and means for rendering .the latch inoperative to hold the valve setting member and valve actuating means in open position when saidstarting connection is open.

' 11. A fuel supply control mechanism comprising the combination with a gas burner provided with a fuel supply connection havmg a main valve movable to shut off the supply of fuel to the burner, of means for normally moving the valve to a closed position;

a valve setting member connected to the valve closing means; a latch mounted upon the valve setting member; a stop movable to engage and disengage the latch; lever means engaging the stop and movable to release said stop to a latch releasing position; a pilot manifold mounted adjacent the burner and provided with a pilot burner, said burner and manifold being adapted to be heated by heat shut off fuel from both the burner and the pilot. r

12. A fuel supply control mechanism com,- prising the combination with a gas burnerprovided with a fuel supply connection hav-' ing a main valve movable to shut off the supply of fuel to the burner, of means for normally moving the valve to a closed position; a valve setting member connected to the valve closing means; a latch mounted upon the valve setting member; a stop movable to engage and disengage the latch; lever means engaging the stop and movable to release said stop to a latch releasing position; a pilot manifold mounted adjacent the burner and provided with a pilot burner, said burner and manifold being adapted to be heated by heat from said pilot burner; a rod extending lon gitudinally through the manifold, one end being secured to the manifold and the opposite end being movable to engage vthe lever means whereby contraction of the manifold when the pilot burner is extinguished will move the rod into actuating engagement with the lever means to release the stop; means for supplying fuel to the pilot from the delivery side of the main fuel valve whereby a closing of said valve will shut off fuel'from both the burner and the pilot; a valve controlled pilot I ply of fuel to the burner, of means for normally moving the valve to a closed position; a vglve setting member connected to thevalve closing means; a latch mounted upon the valve settin member; a stop movable to engage and disengage the latch; lever means engaging the stop and movable to release said stop to a latch releasing position; a pilot manifold mounted adjacent the burner and provided with'a pilot burner, said burner and manifold being adapted to be heated by heatfrom said pilot burner; a rod extending longitudinally through the'manifold, one end being secured to the. manifold, and the opposite end being movable to engage the lever means whereby contraction of the manifold when the' pilot burner is extinguished will move the rodinto actuating engagement with the lever means to release the stop; means for supplying fuel to the pilot from the delivery side of the main fuel valve whereby a closing of said valve will shut off fuel from both the burner and the pilot; and means for conduct-" ing heat fromthe main burner to the rod'to retard the con racting of said rod when the pilot is extinguished.

1 1. A fuel supply control mechanism comprising the combination with a gas burner provided with a fuel supply connection having a main valve movable to shut off the supply of fuel to the burner, of means for normally moving the valve to a closed position; a valve setting member connected to the valve closing means; a latch mounted upon the valve setting member; a stop movable to engage and disengage. the latch; lever means engagingthe stop and movable to release said stop to a latch releasing position; a pilot manifold mounted adjacent the burner and provided with a pilot burner; said manifold being heated by heat from the pilot burner; a rod extending longitudinally through the manifold, one end being secured to the manifold and the opposite end being movable to engage the lever means whereby cooling of the manifold when the pilot is extinguished will move the rod into actuating engagement with the lever to release the stop; pilot fuel supply connections connected to the main supply connection upon opposite sides of the main valve; valve means for directing fuel from either of said pilot fuel connections to the pilot; and means actuated by the valve means for holding the latch in latching engagement with the stop when fuel is supplied froi'n thedelivery sid of the main valve and for releasing said latch for free movement past-the stop when fuel is delivered to the pilot from the supply side of the main va ve.

15. In a fuel supply control mechanism, a

v being slidably movable through the opposite end of the manifold to perm; relative sliding movement between the, rod and said opposite end of the manifold whereby the rod may be moved longitudinally by a contraction of the manifold to engage and impart positive movement to valve setting mechanism mounted exterior-1y of the manifold; and means carried by the main burner and engaging the rod for conducting heat from the gas burner to the. rod independently of heat from the manifold to obtain a differential expansion and contraction of the rod and manifold.

*16.In a fuel supply control mechanism,

- the combination with a pilot burner, a main shut oil valve, and thermostatic means actuated by the pilot burner for automatically releasing the mainshut off valve to a normal, closed position when the pilot burner is extinguished, of a three-Way pilot valve operable to deliver fuel to the pilot burner. from either the supply side or the delivery side -of the main valve whereby a starting supply of fuel from the supplyside of the valve may be closed 0E and the pilot maintained by fuel supplied from the delivery side of the main valve when said main valve is opened, and, I

.a main valve setting detent mounted in con-' nection with the pilot valve and actuated thereby to operative and inoperative positions as the pilot valve is moved to deliver fuel from the delivery and supply sides of the main valve respectively.

In witness whereof, I hereunto set my signature.

GEORGE A. TUCK; 

